As can be seen by reference to the following U.S. Pat. Nos. 3,124,984; 4,598,615; 4,114,481; and, 3,853,026 the prior art is replete with myriad and diverse wrench constructions that are designed specifically for the removal of oil filters.
While all of the aforementioned prior art devices are more than adequate for the basic purpose and function for which they have been specifically designed, these previously patented oil filter wrenches are deficient in a number of salient respects.
To begin with, most of the prior art devices employ a single contractable band to effect the frictional engagement between the wrench and the oil filter; and, should that single component experience structural failure the wrench is rendered inoperative.
This failure to provide redundancy in the prior art filter wrench constructions has created a longstanding problem for users of this type of a device; and, a stated objective of this invention is to cure that glaring oversight.